Gosh, could it be that? Thank you for looking! I'm on a work computer now so cannot check, but I *think* that is a pasting typo.

... hm I will *have* to check, back in a bit :-)

Thank you!

Bless you a thousand time, brother Athanasius!

I just could not see the lack of the trailing comma; my eyes had been looking at the (correct) test output for hours. Once you pointed it out (geez, I should have diffed :-/), I quickly figured it out.

From the Data::Dumper Changes file:

2.160 (Jul 3 2016)
...
    Add Trailingcomma option. This is as suggested in RT#126813.

So I updated my Makefile to specify the Data::Dumper minimum version, and all tests pass on old perls.

Thanks again!